JP2019195076A - Methods of making and using imprint lithography stamp - Google Patents

Abstract

To promote solidification of an imprinting composition.SOLUTION: A stamp for an imprint lithography process comprises an elastomer stamp body including a polysiloxane bulk portion, and a patterned surface comprising a feature pattern for imprinting an imprinting composition. The elastomer stamp body comprises a basic organic amine in an amount of at least 0.1 wt.% based on the total weight of the elastomer stamp body.SELECTED DRAWING: None

Description

  The present invention relates to a stamp for an imprint lithography process, a method of manufacturing such a stamp, and a method of imprinting using a stamp in an imprinting process or the use of such a stamp.

  Imprint lithography is an imprintable composition (also referred to as media or ink) in which a patterning layer such as a masking layer can be solidified (also referred to as curable) on a substrate such as a semiconductor substrate or as an optical layer. ). Subsequently, the imprintable medium is patterned by imprinting the medium with a stamp having a relief pattern on one of its surfaces after or during solidification of the medium. Solidification can be achieved, for example, by exposing the medium to light, such as UV light, to initiate a solidification (curing) reaction in the medium. After this reaction is complete, the stamp is removed from the cured medium, leaving a patterned layer, which serves as, for example, a mask layer on a semiconductor substrate or a functional (optical) layer on a carrier.

  This technique has potential for significant cost savings over traditional optical lithographic processes, especially when large surface areas are required to provide features of a size comparable to or smaller than the wavelength of visible light. In recent years, there has been a great deal of interest. In addition to flat surface imprinting, imprint lithography is a so-called 2.5D surface, i.e. on a contoured surface that includes, for example, one or more protrusions, for example bent protrusions originating mainly from a flat plane. In addition, it can be used to form nanoscale patterns. Such techniques can be applied to photovoltaic cells, nanowires, vertical (external) by creating nanoscale patterns on optical elements such as lenses or, for example, medical implants to promote bone or tissue regeneration. ) Used to pattern cavity surface emitting lasers, medical implants and the like. For this purpose, flat and flexible patterned stamps, such as polysiloxane-based rubber-like stamps, are usually on the contour surface so that the stamp pattern contacts the patterned contour surface. ,Deform. An example of such a stamp is shown in US2008 / 0011934A1.

In at least some imprint lithography applications, imprinting compositions (also referred to as imprint media or imprint inks) based on siloxane sol-gel chemistry are used according to Reaction Scheme I below.

  The reaction that forms the sol-gel system uses an alkoxysilane that undergoes the reaction steps shown in Reaction Scheme I in the presence of an acid or base. Reaction Scheme I shows an acid catalyzed reaction. The alkoxysilane undergoes hydrolysis, which is then a condensation reaction between the two hydrolyzed alkoxysilanes (water condensation reaction) or a condensation reaction between the hydrolyzed alkoxysilane and the unreacted alkoxysilane (alcohol). Condensation reaction), in which case a crosslinked inorganic network is formed. The degree of crosslinking can be controlled by appropriately selecting the alkoxysilane and / or solvent and water content.

  Such a sol-gel reaction is usually an equilibrium reaction in which the equilibrium is shifted towards polymerization (polycondensation) by diffusion of one or more reagents into a stamp such as a PDMS stamp. Due to the sol-gel reaction, when the imprinting composition shifts in this way toward polymerization, it solidifies on the imprinting surface of the stamp and solidifies the reverse of the feature pattern, resulting in a solidified imprinting composition. .

  However, premature solidification of the imprinting composition, for example, prior to its imprinting with an elastomeric stamp, prevents reliable replication of the stamp feature pattern. For this reason, the imprinting composition may include a photoacid generator (PAG) or a photobase generator (PBG) that is activated once the imprinting stamp is placed on the imprinting composition. This can avoid the early start of the described solidified sol-gel reaction.

  The use of PAG or PBG to activate solidification of the imprinting composition is not without problems. First, such compounds are expensive and thus increase the cost of the imprinting composition. Therefore, it is necessary to keep the cost of such an imprinting composition as low as possible, considering that such an imprinting composition is used in application domains where the margin of profit is significantly compressed. Secondly, the inventors also diffuse reaction products produced by such PAG or PBG degradation into the stamp where they contaminate the stamp, eg, stamp material Recognize that it causes a change in the chemical properties of the stamp material. Such contamination is seen to shorten the life of the stamp in the sense that after 50 to 100 imprinting cycles, the stamp can no longer impart a high quality feature pattern on the imprinting composition. It was issued. This is also highly undesirable in the production process where a large volume of product needs to be produced in a single production trial, i.e. no need to replace the stamp.

  The object of the present invention is to reduce, at least in part, at least one of the above drawbacks. This object is achieved by the present invention seeking to provide a stamp, a method of manufacturing such a stamp, and a method of using such a stamp in an imprint process as defined by the independent claims. . The dependent claims provide advantageous embodiments.

  The present invention thus provides a stamp for an imprint lithography process. The present stamp is an elastomeric stamp with its stamp body, which provides some degree of elasticity and flexibility that can be utilized during the imprinting process.

  Providing the stamp body with an amount of at least one basic organic group capable of promoting (supporting or causing) the solidification of the imprinting composition when the stamp contacts the imprinting composition; In the imprinting composition, the need for expensive photosensitive activators (such as PBG) can be avoided, thereby reducing the overall cost of the imprinting composition and The life of the elastomeric stamp is improved because the degradation of the stamp by photodegradation products is also avoided. Thus, the present invention facilitates a more sustainable and cost effective imprint process.

  The stamp of the present invention should be distinguished from a stamp that is modified only on its relief surface with basic organic groups. Such surface modification is performed, for example, by graft functionalization or modification. The stamps of the present invention have rather only bases, or still have bases dispersed in at least a portion of its internal volume or bulk portion. One known drawback of surface modification is that surface modification is often obtained by physical or chemical processes performed after the preparation of the relief surface, and such processes can be characterized by complete feature patterning. It is to destroy sex. This problem is exacerbated for smaller feature patterns. Similarly, the amount of base present on the surface is spatially limited. Thus, the stamp of the present invention has improved feature pattern integrity, improved solidification characteristics, and an easier and more reliable manufacturing method.

  Imprinting compositions in which the stamps of the present invention can be advantageously used are those that can solidify upon exposure to a base such as provided by the basic organic groups of the stamp. Thus, imprinting compositions based on sol-gels, such as those described in the background art, are advantageously used with the stamps of the present invention. The imprinting composition is provided, for example, on a layered substrate. The substrate can be flat or curved.

  When the patterned surface of the stamp of the present invention is contacted with the imprinting composition, solidification of the imprinting composition can occur, and the basic organic group can be incorporated into the imprinting composition due to its solidification. The polymerization reaction can be accelerated. The promotion can be in the form of catalysis. Solidification can be due to the change in pH of the sol-gel imprinting solution, thereby promoting solidification.

  The present invention is intended to include basic groups attached to the stamp, such as covalent bonds, and basic groups that are simply physically retained within the stamp. The latter type can be in the form of a material containing one or more basic organic groups that are sequestered for the stamp body. This material can move through the stamp body.

  While not wishing to be bound by theory, there are several ways in which the stamp can facilitate the solidification process when in contact with the imprinting composition. Thus, if a portion of the amount of basic organic groups located on the patterned surface of the stamp is present, this fraction can be in direct contact with the imprint composition and exert its effect. This may require an impermeable organic polymer bulk portion, which is an impermeable organic polymer bulk portion that interacts with an imprinting composition such as a solvent and basic organic groups. It is impermeable to components consisting of the most notable Lewis acids such as protons or hydronium ions that can promote solidification. However, if the organic polymer bulk portion of the stamp is permeable to the components of the imprinting composition described above, the basic organic group is reached by migration of the components of the imprinting composition to the stamp. So it doesn't have to be on the surface. Alternatively or additionally, the organic polymer bulk portion contains a basic organic group as part of another material that is not chemically bonded to this portion, which allows such material to move the stamp. If configured to allow, solidification can be facilitated by the movement of the material towards the relief surface and even into the imprinting composition.

  The organic polymer bulk portion (or the entire stamp body) may be permeable or porous, preferably permeable or porous. The patterned surface of the stamp is preferably in fluid communication with the organic polymer bulk portion of the stamp. This allows the imprint composition, or one or more solvents or other components thereof, to enter the bulk portion from the imprinting composition, for example, uptake of acids (protons, hydronium ions, etc.), or bases If the organic group is not chemically bonded to the stamp, the replacement of the group from the stamp to the composition can be facilitated.

  Preferably, the basic organic group is an uncharged Lewis base having at least one donor atom selected from the group consisting of oxygen, nitrogen, sulfur and phosphorus. Uncharged bases are optimal for sol-gel based imprinting compositions because they are not incorporated into solidified imprinting compositions. A donor atom in the form of nitrogen is most preferred because it provides a good base with a good pk value while being compatible with other stamp materials. For example, a nitrogen-based Lewis acid is compatible with stamp manufacturing methods that require a stamp material polymerization catalyst that is sensitive to charged species. Examples are Pt or Rh catalysts used to crosslink polysiloxanes to obtain stamps with polysiloxane bulk portions and / or surface layers (see herein below).

  The Lewis acid having a nitrogen donor is preferably an amine. Preferably, these amines have at least 1 sp3 carbon atom, or at least 2 sp3 carbon atoms, or at least 3 sp3 carbon atoms.

  Basic organic groups have a pKa between 8-13. Sol-gel based compositions can be conveniently (at a sufficient rate) solidified with such bases. Preferably, the pKa is between 9-13 or even between 10-13. Bases with a pKa greater than 13 sometimes interfere with the solidification reaction.

である。 In embodiments, the basic organic group comprises a structure according to Formula 8, or a compound according to Formula 8 (such as a basic organic amine):

It is.

  In Formula 8, R1 to R3 are hydrogen, unsubstituted or substituted C2-C20 alkyl group, unsubstituted or substituted C2-C20 alkenyl group, unsubstituted or substituted C2-C20 alkynyl group, unsubstituted or substituted C3-C20 cycloalkyl. Group, unsubstituted or substituted C4-C20 cycloalkenyl group, unsubstituted or substituted C3-C20 heterocyclic group, unsubstituted or substituted C6-C30 aryl group, unsubstituted or substituted C6-C30 alkylaryl group, unsubstituted or substituted Individually selected from C4-C30 heteroaryl groups, provided that R1-R3 are not all hydrogen, and at least two of R1-R3 are the same, unsubstituted or substituted A C3-C20 cycloalkyl group, an unsubstituted or substituted C4-C20 cycloalkenyl group, an unsubstituted or substituted C3-C20 heterocyclic group, Forming part of the substituted or unsubstituted C6~C30 aryl group or an unsubstituted or substituted C4~C30 heteroaryl group.

  In Formula 8, this structure represents an uncharged Lewis base having nitrogen as the donor atom of the lone pair of Lewis base.

  The basic organic amine is a secondary or tertiary amine. For example, in the case of a secondary amine, R1 in Formula 8 is hydrogen and R2 and R3 are branched, unsubstituted or substituted C3-C20 alkyl groups, unsubstituted or substituted C2-C20 alkenyl groups, unsubstituted or substituted A C2-C20 alkynyl group, an unsubstituted or substituted C3-C20 cycloalkyl group, an unsubstituted or substituted C4-C20 cycloalkenyl group, an unsubstituted or substituted C3-C20 heterocyclic group, an unsubstituted or substituted C6-C30 aryl group, Individually selected from unsubstituted or substituted C6-C30 alkylaryl groups, unsubstituted or substituted C4-C30 heteroaryl groups, preferably R2 and R3 are branched unsubstituted or substituted C3-C20 alkyl groups or unsubstituted or Individually selected from substituted C6-C30 alkylaryl groups.

  For example, in the case of a tertiary amine, R1-R3 in Formula 8 is a linear unsubstituted or substituted C2-C20 alkyl group, a branched unsubstituted or substituted C3-C20 alkyl group, an unsubstituted or substituted C2-C20. An alkenyl group, an unsubstituted or substituted C2-C20 alkynyl group, an unsubstituted or substituted C3-C20 cycloalkyl group, an unsubstituted or substituted C4-C20 cycloalkenyl group, an unsubstituted or substituted C3-C20 heterocyclic group, unsubstituted or Individually selected from substituted C6-C30 aryl groups, unsubstituted or substituted C6-C30 alkylaryl groups, unsubstituted or substituted C4-C30 heteroaryl groups, preferably R1-R3 are linear unsubstituted or substituted C2- C20 alkyl group, branched unsubstituted or substituted C3-C20 alkyl group, or unsubstituted Properly it is individually selected from substituted C6~C30 alkyl aryl group.

を含む。 The basic organic group is preferably a structure according to formula 9:

including.

As used herein, N can be a Lewis acid donor atom and X is selected from the group consisting of oxygen, nitrogen, sulfur and phosphorus, thus X also serves as a Lewis acid donor atom. R _{1 to} R ₄ are individually selected from an unsubstituted or substituted aryl group, a linear C 2 to C 20 alkyl group, or a branched C 3 to C 20 alkyl group, preferably R _{1 to} R ₄ are methyl, ethyl Or individually selected from propyl.

R _{5 to} R ₇ are individual organic groups, or identical organic groups containing one or more hydrogen atoms, carbon atoms, oxygen atoms, nitrogen atoms and sulfur atoms containing less than 20 carbon atoms; can do. Preferably there are less than 10 carbon atoms. Preferably, R _{5 to} R ₇ are at least two olefinic bonds of formula 9, and one other double bond (C═N, C═O or C═C), and / or at least one other carbon. -Forming a group with a conjugated system, including carbon triple bonds. Preferably, the conjugated system is an aromatic or heteroaromatic system. Preferably the heteroaromatic system comprises at least two benzene rings.

  These compounds are effective to have two donor atoms that enhance their retention of protons or other Lewis acids. Therefore, these compounds provide a strong base that has no formal charge. These compounds are often referred to as superbasis.

を有する。 A basic organic group (as a special case of formula 9) is a structure according to formula 10:

Have

In Formula 10, R _{1 to} R ₄ are individually selected from a linear unsubstituted or substituted C 2 to C 20 alkyl group, or a branched unsubstituted or substituted C 3 to C 20 alkyl group, preferably R _{1 to} R ₄ are Individually selected from methyl, ethyl or propyl.

  Aromatic groups provide a particularly advantageous base for the strength and compatibility of polysiloxane stamp production.

If the basic organic group is chemically bonded to the elastomeric stamp body, particularly the bulk organic portion and / or the surface layer, among all of the basic organic groups, including those according to formula 8, 9 or 10 , At least one of R ₁ -R ₇ is covalently bonded to the stamp body, organic polymer bulk portion and / or organic polymer surface layer (as described herein below), Has at least one free valence. The bond is then usually to the polymer backbone or side chain group of the stamp body material. Such bonds are due to carbon-carbon, ether, ester amide, and the like. Preferably, the bond is by a carbon-carbon bond, such as a carbon single bond. An exemplary stamp in which an organic basic group is bonded to the polysiloxane in this description provides an example of a bond through a carbon-carbon single bond. If the basic organic group is never chemically bonded to the elastomeric stamp, but is contained within an individual material, at least one free valence is used to hydrogen, or any other suitable or compatible Bind to possible chemical groups.

  In one group of embodiments, the basic organic group is part of a material that is not chemically bonded to the elastomeric stamp body. Such stamps can be made by impregnation of the stamp that provides access to the majority of the various stamp materials used. Preferably, the elastomeric stamp body comprises a material in an amount of at least 0.1% by weight relative to the total weight of the elastomeric stamp body. This achieves a good solidification rate when at least the polysiloxane stamp body and silicon-based sol-gel imprinting composition are used together.

  The basic organic group preferably has a vapor pressure of 0.2 mbar or less at a temperature of 25 ° C. Thus, in the case of an imprinting process performed at room temperature (25 ° C.), the basic organic material (amine) is effectively retained in the stamp, thereby extending the life of the stamp and the volatile material stamp. It is ensured that premature polymerization of the imprinting composition is avoided when the stamp collects in the vicinity of the imprinting composition due to unwanted diffusion from to the imprinting composition.

  In another group of embodiments, if the stamp is not part of a separate material, the basic organic group is covalently bonded to the elastomeric stamp body in the organic polymer bulk portion or the stamp body is in the organic polymer bulk. When including an organic polymer surface layer (120) adhered to the portion, the surface layer includes a patterning layer for at least a portion of the amount of basic organic groups in the organic polymer surface layer.

  In the bonded basic organic group stamp, at least a portion of the amount of basic organic group is located near the relief surface of the stamp. This is present in single layer stamps but also in multilayer stamps. Since the basic group is now fixed in position on the stamp, the stamp's operating mechanism can either promote direct surface contact of solidification, or a Lewis acid component (e.g., from the imprinting solution to the basic organic group site). , Protons or hydronium ions) are reduced to either solidification via transfer. In both cases, the position of the group near the relief surface takes time to move, thus ensuring an acceptable operating speed. Advantageously, with this type of stamp, the use of the stamp does not lose the basic function due to the loss of the basic organic group, since the basic organic group is attached to the bulk portion. Similarly, stamps with improved integrity can be made because such stamps do not need to be loaded with a base after the relief layer is prepared. Such loads often require solvent assisted impregnation, which implies stamp swelling and thus loss of feature integrity.

  The bulk portion is, in some embodiments, a polysiloxane bulk portion, such as a bulk portion based on polydimethylsiloxane (PDMS). PDMS is particularly suitable for use in stamps as polysiloxanes because it provides a fluid permeable elastomeric stamp. PDMS is also per-fluoro-poly-ether, or a mixture thereof. Such materials are at least compatible with basic organic groups in the form of Lewis acids having N donors such as amines or alkylamines. Furthermore, they have good flexibility and permeability or porosity.

  The organic polymer surface layer may comprise or be made of a material selected from the group consisting of at least one polysiloxane, at least one per-fluoro-poly-ether (PFPE), or mixtures thereof. Can be. Again, the polysiloxane can comprise or consist of a material selected from the group consisting of polydimethylsiloxane (PDMS), X-PDMS, or mixtures thereof. Thus, preferably, similarly, the bulk portion is also a polysiloxane bulk portion.

  Multi-layer stamps allow optimization of printing properties by selecting the flexibility of the surface layer, which is different from the flexibility of the remainder of the bulk portion. Thus, the surface layer preferably has a higher Young's modulus than the organic polymer bulk portion. Preferably, both the bulk portion and the surface layer having different Young's moduli are polysiloxanes. Preferably, the surface layer has a higher Young's modulus, preferably it is made from X-PDMS (see below). For example, this embodiment provides that the bulk material is more flexible than the feature pattern-containing surface layer to protect the feature pattern from distortion, for example when imprinting a layer of imprinting composition having the feature pattern. Is advantageous when high is required.

  The surface layer is preferably a fluid permeable layer, which is particularly advantageous if the stamp itself is also fluid permeable. The surface layer can even be a porous layer. Suitable materials for such a surface layer include, but are not limited to, PDMS and PFPE (per-fluoro-poly-ether).

  The stamp further includes a carrier having a polysiloxane bulk portion bonded to the major surface of the carrier at a portion distal from the feature pattern. For example, such a carrier stabilizes the stamp, for example by fixing the carrier to a printing device, and facilitates mounting the stamp on such a device. The carrier is a rigid carrier or a flexible carrier with a limited degree of flexibility to support the deformation of the stamp during use in the imprint process and the stamp on the substrate. Application and / or removal of the stamp from the substrate includes bending of the stamp.

  The stamp according to the above embodiment is manufactured by several suitable manufacturing methods.

That is, the present invention provides a first method for producing a stamp according to any of the preceding claims, the method comprising:
-Providing an elastomeric stamp body having an organic polymer bulk portion and a relief surface;
-Impregnating the elastomeric stamp body with an amount of a material comprising basic organic groups that facilitates solidification of the imprinting composition upon contact with the patterned surface to obtain an impregnated elastomeric stamp body; and Removing at least a portion of the solvent from the impregnated elastomeric stamp body, leaving an elastomeric stamp body comprising a basic organic material.

According to an aspect, there is provided a method of manufacturing a stamp according to any of the embodiments described in the present application, the method comprising:
The step of impregnating the elastomeric stamp body with the organic solvent in which at least 1% by weight of the substance is dissolved in the organic solvent relative to the total weight of the organic solvent, and obtaining the impregnated elastomeric stamp body, and the impregnated elastomeric stamp body Removing the organic solvent from the substrate.

  After this impregnation and solvent removal, a dry impregnated stamp body is obtained. Additional steps may be required to convert this into a final stamp for use in the imprinting process. Such a step involves bonding the dried impregnated stamp body to a carrier at the distal end of the patterned surface. Alternatively, impregnation can be performed as a last step, for example after bonding of the stamp body to the support, so that removal of the organic solvent can result in a stamp ready for use in the imprinting process.

This method has the advantage that virtually any basic organic group is supplied to the preferred stamp, as long as the stamp can be impregnated. Preferably, especially when the elastomeric stamp body is made of polysiloxane, the organic solvent is such as methanol, ethanol, (iso-) propanol, (iso-) butanol, (cyclo) pentanol or (cyclo) hexanol. C ₁ -C ₆ aliphatic alcohols, because the use of such a polar solvent only causes moderate swelling in the stamp body during impregnation, so that the stamp body, when dried, is its original size Because it returns to. Therefore, if such a feature pattern exists before impregnation, feature pattern fidelity is maintained.

  In this method, the material preferably has a vapor pressure that is significantly lower than the vapor pressure of the carrier solvent, for example less than 20%, less than 10%, or even less than 1% of the vapor pressure of the carrier solvent, When the stamp is dried, it is ensured that this material is retained in the stamp.

  A further method of manufacturing a stamp for an imprint lithography process is provided according to some of the embodiments described in this application.

That is, a further method of manufacturing a stamp (14) according to any one of claims 1 to 18 is provided, which method comprises:
-The following mixture:
-One or more precursors each containing at least one first reactive group that can be polymerized to form an organic polymer bulk portion; and-basic organic groups, or protection that does not interfere with the polymerization. Providing a basic organic group-containing substance, and
-Polymerizing the organic polymer bulk portion precursor to form an organic polymer bulk portion surrounded within the material, and optionally the basic organic group if the material contains a protected basic organic group; Deprotecting. This optional step recovers the basic organic group.

In this method, one or more precursors are
A first polysiloxane precursor having at least two groups as at least one first reactive group, wherein each of the at least two groups contains an unsaturated bond, and each of the at least two groups is Having a first polysiloxane precursor selected from the group consisting of alkynes, alkenes, vinyls, aldehydes, ketones and imines; and a second polysiloxane precursor having at least two hydrosilane groups,
These mixtures are
-Further comprising a hydrosilylation catalyst for the catalyst to add hydrosilane groups between unsaturated bonds, wherein the polymerization causes the addition of hydrosilane groups to the unsaturated bonds, thereby forming an organic polymer bulk portion. Including.

  The material further includes at least one second reactive group for reacting with the first reactive group, and the polymerization is caused to react between the first reactive group and the second reactive group. This includes binding the material to the organic polymer bulk portion.

  The method includes the step of dissolving the material in one of the polysiloxane precursors, and then preferably mixing the material having an unsaturated bond with the first precursor, while between the unsaturated bonds. A substance having a group that can be added to is mixed with a second precursor.

  This manufacturing method has the advantage that stamp swelling during loading of the material on the stamp is avoided, but this method is part of a group of amines suitable for use in the impregnation method described above. Only suitable. This is because some substrate materials can poison the platinum catalyst, thereby preventing the hydrosilylation crosslinking reaction from completing to the desired level.

  Suitable materials in the form of amine bases for this process include secondary amines of formula 8, wherein R1 is hydrogen and R2 and R3 are branched unsubstituted or substituted C3-C20 alkyl. Group, unsubstituted or substituted C2-C20 alkenyl group, unsubstituted or substituted C2-C20 alkynyl group, unsubstituted or substituted C3-C20 cycloalkyl group, unsubstituted or substituted C4-C20 cycloalkenyl group, unsubstituted or substituted C3- Individually selected from a C20 heterocyclic group, an unsubstituted or substituted C6-C30 aryl group, an unsubstituted or substituted C6-C30 alkylaryl group, an unsubstituted or substituted C4-C30 heteroaryl group, preferably R2 and R3 are Individually selected from branched unsubstituted or substituted C3-C20 alkyl groups or unsubstituted or substituted C6-C30 alkylaryl groups.

  Suitable amines for this method further include tertiary amines of formula 8, wherein R1-R3 are linear unsubstituted or substituted C2-C20 alkyl groups or branched unsubstituted or substituted C3-C20 alkyls. Group, unsubstituted or substituted C2-C20 alkenyl group, unsubstituted or substituted C2-C20 alkynyl group, unsubstituted or substituted C3-C20 cycloalkyl group, unsubstituted or substituted C4-C20 cycloalkenyl group, unsubstituted or substituted C3- Individually selected from a C20 heterocyclic group, an unsubstituted or substituted C6-C30 aryl group, an unsubstituted or substituted C6-C30 alkylaryl group, an unsubstituted or substituted C4-C30 heteroaryl group, preferably R1-R3 are Linear unsubstituted or substituted C2-C20 alkyl group, branched unsubstituted or substituted C3 C20 alkyl group, or are individually selected from unsubstituted or substituted C6~C30 alkyl aryl group.

Suitable amines further include compounds according to formula 10:

  In Formula 10, R1 to R4 are individually selected from a linear unsubstituted or substituted C2 to C20 alkyl group, or a branched unsubstituted or substituted C3 to C20 alkyl group, preferably R1 to R4 are methyl, Individually selected from ethyl or propyl.

  In an embodiment, the method further comprises the step of grafting or adhering a surface layer comprising a patterned surface to a stamp body comprising a basic organic amine, the surface layer comprising a bulk based on polysiloxane. Has a larger Young's modulus than the part. This has the advantage of avoiding the risk that the surface layer is not exposed to the basic organic amine during curing, thereby preventing the surface layer from achieving its required Young's modulus. The bulk part based on polysiloxane acts as an adhesive between the surface layer and the stamp carrier.

In the inclusion method, the basic precursor further comprises at least one second reactive group capable of reacting with the first reactive group;
The polymerization includes reacting between the first reactive group and the second reactive group, thereby binding the material to the organic polymer bulk portion.

  By this method, the basic organic groups can be effectively bonded to the elastomeric stamp, if present, the organic polymer bulk portion and / or the surface layer.

In this method, preferably
The one or more precursors are
A first polysiloxane precursor having at least two groups as at least one first reactive group, wherein each of the at least two groups contains an unsaturated bond, and each of the at least two groups is A first polysiloxane precursor selected from the group consisting of alkynes, alkenes, vinyls, aldehydes, ketones and imines; and a second polysiloxane precursor having at least two hydrosilane groups,
Including
The at least one second reactive group is selected from the group consisting of alkynes, alkenes, vinyls, aldehydes, ketones, imines and hydrosilanes;
The mixture is
-Further comprising a hydrosilylation catalyst that catalyzes the addition of a hydrosilane group to an unsaturated bond,
The polymerization step involves causing the addition of hydrosilane groups to the unsaturated bonds, thereby forming an organic polymer bulk portion.

  The present invention provides a parts kit for use with a stamp manufacturing method. All features assigned to the stamp component can be used to specify a parts kit. The parts kit can include a manual describing the method of the present invention. The parts kit contains one or more agents, such as to provide a Boc group for protecting the amine (to protect the amine in the form of a carbamate) or to provide a Boc group for protecting other bases. Can do.

  The present invention also provides the use of a stamp according to any one of claims 1 to 19 in an imprint lithography process for forming a patterned layer.

The present invention also provides a method of forming a patterned layer, the method comprising the step of providing a layer of an imprinting composition (12) capable of solidifying under the influence of an organic basic group;
Contacting the layer with the stamp (14) according to any of claims 1-18, so that the relief feature pattern (16) is imprinted on the layer of imprinting composition;
-Maintaining the contact between the imprinting composition layer and the stamp until the imprinted composition reaches the desired degree of solidification; and-removing the stamp from the solidification layer of the imprinting composition; Obtaining a patterned layer.

  Further standards of use or method may be: The pattern forming layer is formed on a substrate that is a flat surface or a curved surface. Since the flexible stamp can follow the surface of the substrate, it is extremely advantageous for patterning a curved substrate. In an advantageous embodiment, the imprint process uses a solidifiable imprinting composition that can be accelerated by a base. More preferably, this is a sol-gel imprinting composition based on sol-gel or silicon chemistry, such as a sol-gel imprinting composition based on alkoxysiloxane. Such sol-gels are due to their chemical properties that can be promoted by a base. In addition, they are often at least partially aqueous, thus providing easy application and removal from rubber / elastomer stamps. This is especially true when the stamp is based on a polysiloxane bulk portion and / or a surface layer or stamp body. The imprinting composition preferably does not include a photosensitive activator for solidifying the imprinting composition. Accordingly, preferably, the imprinting composition based on alkoxysiloxane does not contain a photosensitive activator for the polymerization reaction of alkoxysiloxane.

  Reaching the degree of solidification includes or consists of reaching the desired degree of crosslinking of the alkoxysiloxane in the imprinting composition. Such an imprinting method benefits from the following facts: Acceleration of solidification of the imprinting composition is possible even when using a solidification delayed imprint resist. At the same time, expensive photolabile activators such as PAG or PBG are also included in the imprinting composition, which are also partly described below (eg disclosed in WO2014 / 097096). It is more cost effective than the imprinting method. A further benefit stems from the fact that stamps loaded with basic organic amines can have a long lifetime because they are not degraded by the photolysis products of such photolabile activators.

  During one or more contacting and holding steps (preferably only the holding step), the imprinting composition is heated to the ambient temperature (usually room temperature) as described above. Heating can be done to temperatures above 30 ° C, above 40 ° C, or above 50 ° C, or even above 80 ° C. This is advantageous for faster solidification. This is particularly advantageous when using stamps in which the basic group is not attached to the stamp body and is free to move. Movement can be faster at higher temperatures.

  Preferably, the compound of formula 9 contains one or more substituents, each of which contains at least one vinyl group. More preferably, the one or more substituents are attached to the aromatic system at one of the positions having hydrogen instead of hydrogen.

  The surface layer 120 is made of the same material as the polysiloxane-based body 110, for example, may form an integral part of the polysiloxane-based body 110, or the polysiloxane-based body It may be a separate surface layer made of a material different from 110.

  The surface layer 120 will typically have a thickness of a few millimeters or less, such as 1 mm or less, to ensure that the stamp layer 120 has the desired flexibility properties. In some embodiments, the surface layer 120 has a thickness in the range of 20-50 microns. It will be appreciated that the preferred thickness of the surface layer 120 depends on the material selected for the surface layer 120.

  23. The method of claim 22, wherein at least one of the first and second polysiloxane precursors includes a branch point that is branch T or branch Q of the precursor.

  Embodiments of the present invention have been described in more detail and by way of non-limiting example with reference to the accompanying schematics and schematics, wherein the same reference numerals are used throughout the drawings to denote the same or similar parts. ing.

Figure 2 illustrates various steps of an imprint lithography method. Figure 2 illustrates various steps of an imprint lithography method. Figure 2 illustrates various steps of an imprint lithography method. Figure 3 illustrates a patterned stamp for use in an imprint lithography process.

  In the context of this application, some terms have the following meanings:

  The term elastomer has its usual meaning in the chemical field. In general, an elastomer is an amorphous polymer that exists above its glass transition temperature, has viscoelasticity and weak intermolecular forces, and generally has a low Young's modulus and high failure strain compared to other materials. Amorphous polymer. This term includes rubber. The elastomer is usually a thermosetting system (which requires vulcanization), but may be thermoplastic. Long polymer chains are usually cross-linked (ie, vulcanized during curing, for example). Elasticity is due to the long chain's ability to reconfigure itself to distribute the applied stress. Covalent cross-linking ensures that the elastomer returns to its original configuration when the stress is removed.

  In order to promote (catalyze or assist) the solidification of imprinting solutions such as sol-gel based imprinting solutions, the inclusion of basic organic groups (amines) within the stamp (volume) Has the distinct advantage of. For example, imprinting compositions no longer require the presence of a polymerization catalyst, such as an activator such as PAG or PBG, which significantly reduces the cost of such compositions and the intended use of polymerization activators. Activation and subsequent solidification of the composition is avoided, thus improving its shelf life. Furthermore, since there is no such activator, the formation of degradation products of such activator during its activation is avoided. Due to the absence of such decomposition products, the stamp material is prevented from being decomposed by reaction with such decomposition products, thereby extending the life of the stamp.

  When referring to a basic organic group, this is a group or function that is part of the stamp body, or part of an individual substance, including one or more of such groups, via a chemical bond. It is intended to include a group, and this material is present in the volume of the stamp body. Thus, when referring to an elastomeric stamp loaded with basic organic groups, this refers to an embodiment in which the basic organic groups are physically or chemically bound within the stamp body, i.e. in the volume of the stamp. It is intended to include. This chemical bond includes, for example, at least one of absorption or adsorption by intermolecular forces, hydrogen bonds, ionic and covalent bonds, or combinations thereof. In some embodiments, the basic organic group (amine) is reversibly attached to the stamp to facilitate reversible (partial) desorption of the basic organic amine from the stamp material and imprinting that contacts the stamp. Accelerate the polymerization reaction or catalysis in the composition. Fluid permeable elastomeric stamps are typically permeable to gases and liquids. The fluid permeable elastomeric stamp may be a porous stamp (ie having an open hole or an open channel leading to it), but this is not necessary in this case. Examples of (fluid permeable) elastomeric stamp materials include polydimethylsiloxane (PDMS) and PFPE perfluoropolyethers, but embodiments of the invention are not limited to these examples.

  The term basic organic group is intended to include organic groups or functional groups that act as Arrhenius bases or Lewis bases. A basic organic group is a conjugate base of an acid. Preferably, this group has no formal charge. This group can be a basic organic amine.

The term Lewis base has its usual meaning in chemistry. Thus, according to the instruction book, a Lewis base is a chemical species that reacts with a Lewis acid to form a Lewis adduct. Next, a Lewis base is any chemical species that donates a pair of electrons (lone electron pairs) to a Lewis acid to form a Lewis adduct. In the adduct, the Lewis acid and the Lewis base share an electron pair supplied by the Lewis base. For example, OH ^- and NH _3, since it is possible to donate electrons lone pair, they are Lewis bases. OH ⁻ is an example of a Lewis base having a formal negative charge, and NH ₃ is an example of an uncharged Lewis base having no formal charge. A Lewis base has its pair of electrons available for donation located at the donor atom. Many examples of donor atoms exist: for example oxygen in ethers, such as nitrogen in amines, alkylamines or pyridines, such as sulfur in sulfides, and phosphorus in phosphines or alkylphosphines.

The term amount is an effective amount in the sense that when the stamp contacts the imprinting composition, it means that there are enough basic organic groups to affect solidification. This amount is specified as the number (in moles) of basic organic groups (each capable of binding to one equivalent of proton) per weight of the stamp body. For example, in moles per gram of the stamp body, the amount of groups ^{is> 1 -6,> 0.5} -5,> 1 -5,> ^{0.5 -4, or> 1 -4,} or > also becomes ^{0.5 -3.} In general, the higher the amount, the faster the solidification can work. If a stamp having basic groups therein is prepared using any of the in situ intervening procedures described herein below (as opposed to the impregnation procedure), this amount will be The fraction has an upper limit because it is too large for the resulting suitable rubber body. Suitable amounts, ^<(In the case of a group having a molar weight 30 to 100) ^{1 -3} or ^{<5 -4, <5 -4} or ^{<2.5 4} (molar weight of group with 100-200 Case), < ^3-4 or < ^1.3-5 (for groups having a molar weight of 200-300), < ^2.5-4 or < ^1.2-4 (molar weight of 300-400) for group), or ^{<2 -4} or ^{<1 4} (mol wt can be a case of groups) having 400-500. Using the molar weight of the group can be used and an amount different from the weight percentage can be calculated.

  If basic organic groups are present as part of a separate substance, their amount is given by the given weight of the substance per weight of the stamp body, taking into account the number of basic organic groups per substance molecule. is there. For example, the organic polymer bulk portion comprises at least 0.1% by weight of material relative to the total weight of the organic polymer bulk portion.

  Accordingly, at least some embodiments of the present invention are based on the total weight of the elastomeric stamp to catalyze the sol-gel reaction in an alkoxysilane based imprinting composition used in imprint lithography techniques. It relates to providing a stamp comprising (loaded with) basic organic groups in an amount of at least 0.1% by weight. In this case, one preferred stamp is one in which the organic polymer bulk portion is polysiloxane.

  Conformal based on soft (flexible) imprinting stamps (such as substrate conformal imprint lithography (SCIL)) to illustrate how the stamps of the present invention work on imprinting compositions An embodiment of an imprint lithography technique known as imprint lithography (where a flexible fluid permeable mold or stamp is used) is described herein below. The reader is referred to the following disclosure for more detailed information regarding the apparatus (WO2003 / 099463), methods and resists (WO2008 / 053418 and WO2014 / 097096). A major advantage of conformal imprint lithography is that the flexibility of the stamp allows complete contact between the stamp pattern and the surface, so that the microstructure is irregular (eg, non-planar) surfaces and curved surfaces. It can be duplicated on top.

  FIG. 1 schematically illustrates an exemplary embodiment of an imprint lithography process according to the present invention. In Step A, silicon substrate, silicon on insulating substrate, GaAs substrate, GaN substrate, AlGaN substrate, metal substrate such as Al or Cr substrate, polymer substrate such as PMMA substrate, glass substrate, ceramic substrate such as sapphire The major surface of the substrate 10, which is any suitable carrier, such as is coated with a layer of curable imprintable composition 12. This coating can be done, for example, using spin coating, but other techniques can be used if desired.

  The chemical nature of the imprinting composition 12 is not particularly limited. For example, any suitable sol-gel imprinting composition is used for this purpose. The sol-gel imprinting composition based on alkoxysilane is particularly suitable for providing a solidified pattern-forming layer having the desired properties and using, for example, a spin coating method, a doctor blade method, an inkjet method, etc. Such imprinting compositions are particularly suitable since they are known to exhibit desirable properties for easy deposition of the imprinting composition, in which case the polycondensation of the silane compound in the imprinting composition 12 Is activated as needed to ensure that the process window for imprinting the imprinting composition with the imprinting stamp is not narrowed by premature polycondensation of the silane compound in the imprinting composition be able to. Such compositions are described, for example, in WO2008 / 053418 or WO2014 / 097096.

（式中、Ｒ_１〜Ｒ_８は、Ｃ_１〜Ｃ_６線状又は分岐状アルキル基、及びフェニル基からなる群から個々に選択される）。このようなシラン化合物の特に好適な例は、式４〜７の化合物：

によって定義される。 In embodiments, the imprinting composition is based on a silane monomer of Formula 1, Formula 2, or a combination thereof:

(Wherein R _{1 to} R ₈ are individually selected from the group consisting of C _{1 to} C ₆ linear or branched alkyl groups and phenyl groups). Particularly suitable examples of such silane compounds are compounds of formulas 4-7:

Defined by

  The imprinting composition is based on a first silane compound that is Formula 1 and a second silane compound that is Formula 2. This has the advantage that the amount of crosslinking can be controlled by changing the ratio between the first and second curable compounds. Usually, increasing the ratio to the first curable compound decreases the crosslink density in the network formed during the polycondensation reaction. In order to obtain the most desirable crosslinking density, the molar ratio of the first silane compound to the second silane compound is in the range of 5: 1 to 1: 5.

  In a particularly preferred embodiment, the first silane compound is MTMS. It has been found that when MTMS is combined with a completely inorganic silane compound, i.e. a silane compound according to Formula 2, undesirable shrinkage of the ink composition can be significantly avoided upon solidification. Particularly suitable second silane compound embodiments for use in combination with MTMS are TMOS and TEOS.

  In order to achieve the desired degree of polymerization in the imprinting composition before it is deposited, i.e. to adjust the viscosity of the imprinting composition to facilitate its deposition on the substrate 10, The pH of the composition is set in the range of 3-5, preferably 3.5-4.5. In particular, about pH 4 is preferable. The pH is set using any suitable protic acid, for example, an organic acid such as acetic acid or formic acid, or an inorganic acid such as hydrochloric acid.

  The majority of the acid content usually evaporates from the imprinting composition upon drying, which occurs after layer formation and before application of the stamp, so the presence of such acids is usually due to the base of the present invention. Note that it does not interfere with the loaded elastomeric stamp. Similarly, it is not necessary to bring the pH of the ink composition to the pH of the organic base in the stamp. As long as the pH of the ink composition is increased to an alkaline pH (ie, pH> 7), rapid polycondensation of the imprinted alkoxysilane-containing material can be achieved.

（式中、Ｒ_９は、Ｃ_１〜Ｃ_６線状又は分岐状アルキル基、及びフェニル基からなる群から選択され、ｎは、少なくとも２の値を有する正の整数である）をさらに含む。特定の有利な実施形態では、ｎは、２、３、４又は５である。 The ink composition is an inhibitor of polycondensation according to Formula 3 that competes with the silane compound during the polycondensation reaction as shown in Reaction Scheme I:

Wherein R ₉ is selected from the group consisting of a C ₁ -C ₆ linear or branched alkyl group and a phenyl group, and n is a positive integer having a value of at least 2. In certain advantageous embodiments, n is 2, 3, 4 or 5.

  In particular, advantageous examples of polyethylene glycol monoethers of formula 3 include diethylene glycol monomethyl ether (EEOL), diethylene glycol monoethyl ether, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, tetraethylene glycol monomethyl ether and tetraethylene. Glycol monoethyl ether is included.

  At a pH of 3-5, preferably at a pH of 3-5-4.5, more preferably at a pH of about 4, the compound of formula 3 reduces the level of completion of the polycondensation reaction between silane compounds in the ink or composition. It has been found that the equilibrium of the polycondensation reaction is shifted more towards the oligomer / monomer side of this equilibrium. In particular, a silane oligomer comprising a compound of formula 3 is formed. Such polycondensation retarders can be used, for example, to increase the shelf life of the imprinting composition and adjust its viscosity, thus making the imprinting composition more effective on the surface of the substrate being imprinted. Can be applied automatically. Stamps loaded with basic organic amines according to embodiments of the present invention are capable of rapidly shifting the equilibrium reaction in such imprinting compositions toward polycondensation in the presence of such inhibitors. It was found that there was.

である。 In embodiments, the ink or composition further comprises one or more additives that are not involved in the polycondensation reaction but are used to improve the characteristics of the ink or composition. For example, the ink or composition contains additives that improve the film forming properties of the ink. Non-limiting examples of such additives include 1-ethoxy-2- (2-ethoxyethoxy) ethane (EEE):

It is.

  Such imprinting compositions have, as non-limiting examples, compositions selected from the ranges specified in Table I. In Table I, when referring to weight percentages (% by weight), this is relative to the total weight of the imprinting composition, unless otherwise specified.

  Other suitable compositions can be solidified by stamp basic organic groups as those that can be solidified by changes in pH or by changes in other components such as metals or other ions involved in the solidification reaction. It will be obvious.

  Advantageously, the imprinting composition 12 does not require the presence of a polycondensation activator such as PAG or PBG. This is because a stamp 14 loaded with an organic base is used, which can catalyze the sol-gel condensation reaction of imprinting based on alkoxysilanes, as described in more detail below. Thus, the imprinting composition increases the viscosity of the imprinting composition and, as a result, reduces the ability of the stamp 14 to imprint the imprinting composition into the desired pattern. Almost unaffected. The flexible stamp 14 has a relief feature pattern formed by spatially isolated protrusions 16, as shown in step B, and is imprinted on the curable imprintable medium 12, Thereby, the reverse pattern is transferred to this layer. Although not explicitly shown, imprinting of the deposited curable imprintable medium 12 using the flexible stamp 14 may cause a portion of the solvent system to be cured as desired. This is done by a drying step that evaporates to improve the viscosity of the possible imprintable medium 12.

  Next, as illustrated in Step C, the imprinting stack (substrate + imprinting + flexible fluid permeable elastomeric stamp) has an organic (amine) base in the flexible fluid permeable elastomeric stamp 14, Maintained in contact so that the polycondensation reaction can be catalyzed to cause solidification (sol formation) of the imprinting composition. In some cases, the imprinting stack is heated to further accelerate the polycondensation reaction. When this polymerization reaction is complete, the stamp 14 is removed in step D, leaving the pattern portion 18 on the substrate 10 behind.

  When such a curable imprinting composition is used, a cured pattern-forming layer having a high inorganic content and a high crosslinking density can be realized, so that the curable imprinting composition still has optical properties. It is used to form multilayer structures such as controlled three-dimensional structures, such as light emitting diodes, interferometers, photonic crystals and the like. Such a three-dimensional structure is generated by filling or planarizing the patterned layer 20 by depositing a planarizing material 22 on the patterned layer 20, as shown in FIG. If necessary, excess material is removed by etching or polishing. The planarizing material 22 is any thermally decomposable material such as a thermally decomposable polymer (TDP). Non-limiting examples of TDP are polynorbornene or polystyrene. Alternatively, the planarizing material 22 is soluble in a specific solvent. In general, any planarization material 22 that can be selectively removed from the formed multilayer structure without damaging the patterned layer formed from the curable imprintable composition is used.

  A non-limiting example of a method for producing such a three-dimensional structure is shown in FIG. In step A, the planarization layer 30 is formed on the substrate or carrier 10 as already described. The patterned portion 20 of the planarization layer 30 may be applied to imprint lithography (eg, substrate conformal imprint lithography, SCIL, using a curable imprinting composition 12 according to the method illustrated in FIG. ). The pattern 20 is filled, i.e. planarized by the filling material 22. In step B, the next layer of curable imprinting composition 12 is deposited on the planarizing layer 30 of step A in any suitable manner, for example by spin coating, dispensing or doctor blade. Applied.

  The curable imprinting composition 12 deposited in step B is then suitably patterned fluid permeable elastomer after aligning the stamp with respect to the substrate 10 as shown in step C. Embossed by the stamp 14. In step C, the imprinting orientation of the stamp 14 by the substrate 10 is rotated by 90 ° with respect to the imprinting orientation used to form the first patterning layer 20. It will be appreciated that other orientation rotation angles are equally feasible. Subsequently, the curable imprinting composition 12 is solidified (densified), eg, as shown in FIG. 1, to form a solidified portion 20 ′, as shown in Step D. Obviously, the formation of the solidified portion 20 'is completed after removing the stamp 14, i.e., as already discussed, by completing the inorganic polymerization reaction. When the stamp 14 is removed, the high density portion 20 ′ remains on the planarizing layer 30 in Step A. The newly formed patterned layer is planarized again as shown in Step E, and then additional layers are formed by repeating Steps B-E. The height of the patterned portion of the patterned layer is reduced using an additional processing step, for example, by reactive ion etching.

  The filler material 22 can then be removed as shown in step F, for example by dissolving the filler material 22 in a suitable solvent or by pyrolysis, thus obtaining a stack structure. . The sol-gel system based on alkoxysilanes can withstand most of the solvents required to dissolve the planarizing material 22 in its sol state and withstand high temperatures up to 600 ° C or 1000 ° C. This makes it particularly suitable for the use of thermally decomposable compounds such as TDP, so it can be said that sol-gel systems based on alkoxysilanes are particularly suitable as imprinting for applications in this method.

  For example, if a layer on the substrate 10 is patterned using the imprint structure as a mask, the residual imprint structure needs to be removed from the substrate 10, for example. The imprint structure is removed by any suitable etching technique, such as reactive ion etching.

  FIG. 4 schematically illustrates an exemplary embodiment of stamp 14 (eg, a fluid permeable elastomer) in more detail. Stamp 14 typically includes a body 110 that is preferably made from a polysiloxane-based material. The following description relates to a polysiloxane (stamp having a bulk portion, but other elastomers or rubber materials may be used for the bulk portion. Those skilled in the art can apply such other materials without problems. In the following examples, the polysiloxane bulk part will be described, an example of such a polysiloxane based material is PDMS (polydimethylsiloxane), but similar It should be understood that polysiloxane-based materials are also contemplated, such as polysiloxanes in which at least some of the methyl groups have been replaced by larger alkyl groups, such as ethyl, propyl, isopropyl, butyl groups, and the like. Alternatively, materials based on polysiloxane are, for example, WO2009 / 147602A Including a rubber-like material based on T-branched and / or Q-branched polysiloxanes, as described in US Pat. It is noted that three-way branched chains, i.e. networks, similarly, Q-branched polysiloxanes, for example when crosslinked by linear polysiloxanes, contain four-way branches, i.e. networks. The branched material can be used to make a stamp body portion having a higher Young's modulus, as will be shown below in the present invention.

  The stamp 14 further includes a surface layer 120 having a pattern 16 (eg, fluid permeable), as shown in the inset expanded above in FIG. However, this layer is not necessary for the practice of the present invention. The surface layer 120 is made of the same material as the polysiloxane-based body 110, for example, may form an integral part of the polysiloxane-based body 110, or the polysiloxane-based body It may be a separate surface layer made of a material different from that of 110. In embodiments where the surface layer 120 is made of such a different material, the surface layer 120 is grafted onto or adhered to the polysiloxane-based body 110. The In an embodiment, the polysiloxane-based body 110 is adhered to the surface layer 120, for example, prior to curing, so that the body 110 can be used as an adhesive or glue between the surface layer 120 and the carrier 130. Works. In embodiments where a more rigid surface layer 120 is desired compared to, for example, a polysiloxane-based body 110, a different surface layer 120 is contemplated, for example, to prevent distortion or collapse of features in the feature pattern 16. Such a distortion of collapse in the soft surface layer 120 can occur, for example, when the feature size of the feature pattern 16 is particularly small, eg, less than 0.5-1 microns.

  In an embodiment, the surface layer 120 has a higher Young's modulus than the body 110 based on polysiloxane. The dimensions of feature 16 are, for example, in the range of 200 nm to 2 microns, and rubbery materials having a Young's modulus in the range of 7-11 MPa such as rigid PDMS are contemplated, while the dimensions of feature 16 in the range of 1 nm to 200 nm. For stamps having a rubbery material having a Young's modulus in the range of 40-80 MPa, such as fairly rigid PDMS (sometimes referred to as X-PDMS) is contemplated. Another example of a suitable material for the surface layer 120 is PFPE (per-fluoro-poly-ether). Other suitable polymeric materials for the surface layer 120 having the desired Young's modulus will be readily apparent to those skilled in the art. If stated in a misleading manner, the reported Young's modulus is a standard hardness test in accordance with the ASTM D1415-06 (2012) standard with rigid balls penetrating rubber material under the conditions specified by the standard. It is noted that it was determined by

  The surface layer 120 will typically have a thickness of a few millimeters or less, such as 1 mm or less, to ensure that the stamp layer 120 has the desired flexibility properties. In some embodiments, the surface layer 120 has a thickness in the range of 20-50 microns. It will be appreciated that the preferred thickness of the surface layer 120 depends on the material selected for the surface layer 120.

  The polysiloxane-based body 110 is thicker than the surface layer 120 to provide flexibility to the stamp 14, particularly when the polysiloxane-based body 110 has a lower Young's modulus than the surface layer 120. For example, the polysiloxane-based body 110 has a thickness in the range of 0.1-5 mm, such as 0.5-2 mm.

  The features of feature pattern 16 have a feature size in the range of a few microns to a few nanometers, i.e. feature 122 defines a nanopattern, but it is also feasible to use a larger feature size. . The surface layer 120 has a Young's modulus adjusted to the intended size of the stamp feature 122 to be produced. For example, for relatively large feature sizes, eg, from 500 nm up to a few microns, eg, 2 microns or 5 microns, a relatively soft rubbery material, eg, in the range of 2.5-5 MPa such as soft PDMS. A rubber-like material having a Young's modulus is used. This is because relatively large sized features are relatively difficult to collapse due to surface tension during the stamp manufacturing or imprinting process. Such collapse is usually related to the distance between features, and a small distance between features causes over-flexible features to adhere together under the influence of surface energy. Note that the distance between features is usually not necessarily related to the feature size. Thus, where smaller sized features (and / or smaller inter-feature distances) are required, a stiffer rubbery material is contemplated to prevent collapse of smaller sized features due to the surface tension described above. Is done.

  The feature pattern 16 is formed on the surface layer 120 in any suitable manner. The feature pattern 16 is formed using known techniques such as electron beam patterning (and reactive ion etching) etching or interference lithography (and subsequent etching).

  A stamp 14 is attached and, for example, adhered to a carrier or support 130 to improve the stability of the stamp 14. Preferably, the carrier or support 130 is rigid and has a limited degree of flexibility. Thus, the support is at least more rigid than the stamp or stamp body so that the support can support the stamp. The support 130 is preferably fluid impermeable so that this material cannot diffuse from the stamp 14 to the support 130. The support 130 is made of, for example, a suitable (co) polymer such as glass, polymethyl methacrylate (PMMA), polyethylene terephthalate (PET), other plastics, metals or metal alloys. In order to prevent the imprinting composition 12 from flowing out when the substrate 10 contacts the stamp 14, the support 130 includes one or more rubber seals 140 in the edge region of the rigid support 130, thereby As the feature pattern 16 is pressed against the imprinting composition 12, force is applied from the substrate 10 to a portion of the imprinting composition 12.

  The elastomeric stamp 14 is loaded with basic organic groups in any suitable manner.

  The method of the first example is by impregnation. In this method, the stamp 14 has a basic organic group (such as a basic organic amine) in an organic solvent for a period of time, such as a period ranging from 30 minutes to 12 hours, preferably a period ranging from 1 hour to 6 hours. Soaked in a solution of the substance containing. This material is preferably present in the organic solvent in an amount of at least 1% by weight, based on the total weight of the organic solvent. For example, the basic organic amine is present in an amount ranging from 1 to 5% by weight, based on the total weight of the organic solvent. The amount of material in the organic solvent is preferably such that when the material is loaded onto the stamp 14, the amount of material in the stamp 14 after removal of the organic solvent is equal to the total weight of the stamp 14 (ie, the bulk material 110 and the surface layer). The total weight of 120) is at least 0.1% by weight. If the amount of material in the stamp 14 is less than 0.1% by weight relative to the total weight of the stamp 14, the polymerization of the imprinting composition catalyzed by the basic organic group is too slow. There is no specific requirement on the upper limit for the total amount of material in the stamp 14, but an amount of material greater than about 3% by weight relative to the total weight of the stamp 14 no longer affects the polymerization rate of the imprinting composition 12. As a result, in some embodiments, the amount of material in the stamp 14 ranges from 0.1 to 3% by weight, based on the total weight of the stamp 14.

  Many organic solvents are used to dissolve the material and then the stamp 14 is dipped. Polar solvents are particularly preferred. Among such polar solvents, alcohols such as methanol, ethanol, propanol, iso-propanol, butanol, pentanol, n-hexanol and cyclohexanol moderately swell stamp 14 (eg, polysiloxane bulk portion). It is preferable because it only needs to be done. Such swelling should be avoided as much as possible as it can distort the feature pattern 16, while excessive swelling does not become fully reversible when the stamp 14 is dried, and therefore the This results in a distorted stamp 14 that is not suitable for use in a printing process.

  After the dipping step, the soaked stamp 14 is washed with water to remove residual solvent from the stamp. This washing is repeated any suitable number of times. Following the optional cleaning step, the soaked stamp 14 is dried to remove organic solvent from the stamp, thereby leaving behind the loaded material on the stamp 14. Such drying is performed at a high temperature, for example, in an oven, and the drying time of the elastomer stamp 14 is shortened. However, in embodiments, the stamp 14 is dried by exposing it to ambient or reduced pressure at room temperature (25 ° C.) for at least 12 hours, such as 16 hours, 24 hours, or 48 hours, Residual organic solvent is evaporated from the stamp 14.

  This embodiment of the impregnation method is used to impregnate the entire stamp 14 with material. In an alternative embodiment, only the (polysiloxane) bulk portion 110 of the stamp 14 is impregnated in this manner, and a separate surface layer 120 is grafted or adhered to the (polysiloxane) bulk portion 110 after impregnation. The surface layer 120 is produced prior to the production of the polysiloxane bulk portion 110 that is used as an adhesive between the surface layer 120 and the carrier 130. In this embodiment, the material diffuses from the polysiloxane bulk portion 110 and the surface layer 120 to the surface layer 120.

  It is particularly advantageous if at least the bulk portion 110 and / or the surface layer 120, or even the entire stamp, is fluid permeable, at least by the impregnation method described herein. The impregnation can then be done quickly.

  A wide range of materials with basic organic groups (and especially Lewis bases with nitrogen donors) are used to impregnate the elastomeric stamp 14 using the impregnation method described above, followed by reference to FIGS. Has been found to catalyze the polymerization of the imprinting composition 12 in a lithographic imprinting process, such as the process described above.

  The exemplary materials 1-36 listed in Table 2 were successfully loaded onto the PDMS stamp by impregnation. PDMS stamps loaded with materials 1-18 and 20-39 are based on alkoxysiloxanes at a faster rate at room temperature compared to the rate achieved with the same stamp loaded without the corresponding material loaded. Was successfully used to solidify the imprinting composition. Note that compound 19 is not a base and this one die did not accelerate the imprinting composition. This base is included in the table for other purposes, as described herein below. All the compounds cause solidification of the 55 to 150 nm thick imprinting solution on the silicon substrate within 1 to 5 minutes at room temperature (RT) after contacting the stamp with the imprinting solution. For comparison, a similar thickness imprinting solution on silicon was cured by stamp without base for about 40 minutes at room temperature and 10 minutes at 50 ° C.

  This clearly demonstrates that these materials are selected from a wide range of bases with a pKa greater than 7. In general, it was observed that the stronger the base (the higher the pKa or the lower the pKb), the faster the imprinting composition based on the alkoxysiloxane occurs. Preferably, the base has a pKa between 8-13. More preferably, the pKa is between 10-13. Based on their pKA values known in the art, one skilled in the art can select an appropriate base of the present invention.

が含まれる。 A wide variety of suitable materials include, but are not limited to, compounds having Formula 8:

Is included.

In Formula 8, R _{1 to} R ₃ are hydrogen, unsubstituted or substituted C _{2 to} C ₂₀ alkyl group, unsubstituted or substituted C _{2 to} C ₂₀ alkenyl group, unsubstituted or substituted C _{2 to} C ₂₀ alkynyl group, substituted or unsubstituted _C 3 _{-C 20} cycloalkyl group, an unsubstituted or substituted _C 4 _{-C 20} cycloalkenyl group, an unsubstituted or substituted _C 3 _{-C 20} heterocyclic group, an unsubstituted or substituted _C 6 _{-C 30} aryl group , unsubstituted or substituted _C 6 _{-C 30} alkylaryl group, but individually selected from unsubstituted or substituted _C 4 _{-C 30} heteroaryl group, provided that the _R 1 to R ₃ is that not all of the hydrogen Condition.

At least two of R _{1 to} R ₃ are the same unsubstituted or substituted C _{3 to} C ₂₀ cycloalkyl group, unsubstituted or substituted C _{4 to} C ₂₀ cycloalkenyl group, unsubstituted or substituted C _{3 to} C _20. heterocyclic group, part of an unsubstituted or substituted C ₆ -C ₃₀ aryl group or an unsubstituted or substituted C ₄ -C ₃₀ heteroaryl group is formed, i.e., form part of the same ring structure.

The term “substituted” means that the hydrogen of the compound or group is halogen (F, Br, Cl or I), hydroxy group, nitro group, cyano group, amino group, azide group, amidino group, hydrazino group, hydrazono. group, carbonyl group, carbamyl group, a thiol group, an ester group, carboxyl group or its salt, a sulfonic acid group or its salt, a phosphoric acid group or salts _thereof, C 1 _{-C 20} alkyl _group, C 1 _{-C 20} alkoxy group, C ₂ -C ₂₀ alkenyl _group, C 2 _{-C 20} alkynyl _group, C 6 _{-C 30} aryl _group, C 7 _{-C 30} arylalkyl _group, C 1 _{-C 20} heteroalkyl _group, C 1 _{-C 20} heteroaryl group , _C 3 _{-C 20} heteroarylalkyl _group, C 3 _{-C 30} cycloalkyl _group, C 3 _{-C 15} cycloalkenyl _group, C 6 _{-C 15} cycloalkyl It refers to substituted by Le group, C ₂ -C ₂₀ heterocycloalkyl group and a substituent selected from the combinations thereof.

In an embodiment, only one of R _{1 to} R ₃ is hydrogen, ie the material is a secondary amine. In yet another embodiment, none of R ₁ -R ₃ is hydrogen, ie the basic organic amine is a tertiary amine.

  In the present invention and the embodiments described herein, the stamp, stamp body and / or surface layer can be fluid permeable. As shown herein above, such permeability can be advantageous, for example, in the case of stamps made by an impregnation method.

  An alternative method of loading the basic organic group onto the stamp 14 is by surrounding the basic organic group in the stamp body during its formation. In this example, such formation is by, for example, curing or crosslinking the base material with additional materials to form the polysiloxane bulk portion 110 of the stamp body. Thus, the polysiloxane-based bulk portion 110 in this method is formed by reacting a reactive, eg crosslinkable, polysiloxane-based material with the base material, which preferably includes cross-linking. The

  This alternative enclosure method, and the stamps produced by this method, avoids the swelling of the stamp 14 due to solvent impregnation, so that the high quality feature pattern 16, i.e. features that are not distorted by such swelling action. It has the advantage of being easier to produce stamp 14 with pattern 16. It also saves stamp manufacturing time.

In the case of polysiloxane bulk partial stamps, suitable substrate materials are those that have free alkyne or alkene (unsaturated bonds) groups, such as vinyl groups, capable of reacting with the hydrosilane portion of the hydrosilane modified polysiloxane. Others such as aldehydes and ketones can be used, which lead to different cross-linking chemistries, but the principle of this method is no different from using alkenes. Examples of such crosslinked polysiloxanes include HMS-301 and HMS-501, both of which are trimethylsiloxy-terminated methylhydrosiloxane-dimethylsiloxane copolymers marketed by the company Gelest, Incorporated. Examples of polysiloxane bulk moieties modified with free alkene groups are the family of Sylgard®, products marketed by Dow Corning Corporation, which have polydimethylsiloxane oligomers or vinyl end groups A polymer (an example is shown by Formula 11 representing a linear vinyl-terminated functionalized polysiloxane, where n is selected as needed).

Thus, the vinyl group of the vinyl-substituted moiety can be reacted with a hydrosilane moiety, for example according to Reaction Scheme II, describing a so-called hydrosilylation reaction catalyzed by a hydrosilylation catalyst. Hydrosilylation in this case involves the addition of a hydrosilane group to the unsaturated bond of the vinyl group. Hydrosilylation is known per se and will not be described in detail here. Useful catalysts are described herein below.

  It will be apparent that the opposite situation can also be used where the base material is a modified hydrosilane and the reactive polysiloxane is an alkene modified polysiloxane.

  According to this method, the substance (including basic organic groups) is in an amount of at least 0.2% by weight relative to the total weight of the polysiloxane-based material, for example 0.2% relative to the total weight of the polysiloxane-based material. It is dissolved in the polysiloxane-based material in an amount ranging from 5% to 5% by weight. The base material is one of the precursors to the polysiloxane bulk portion of the stamp body. An example of a suitable polysiloxane bulk portion substrate is, for example, soft PDMS (having a low Young's modulus of less than 10) marketed by Dow Corning Corporation under the trade name Sylgard®, or by reference herein. X-PDMS specially designed to have a larger Young's modulus, for example greater than 20, as described in WO2009 / 147602, incorporated in the literature. All the base materials mentioned have vinyl groups as reactive groups that polymerize. In Sylgard, the base material has a linear polymer or oligomeric polysiloxane chain (chan), whereas in X-PDMS precursor base material, multiple branch points (3 or 4 branch points) are vinyl groups. There is a branch point including

  The base material of the polysiloxane bulk portion containing the substance dissolved therein is subsequently allowed to stand for at least 6 hours, such as between 8 and 12 hours. The polysiloxane-based material containing the substance dissolved therein is allowed to stand for this period at an elevated temperature to facilitate the distribution of the substance in the polysiloxane-based material. A suitable temperature is selected in the range of 30 ° C to 100 ° C, for example 50 ° C.

  The cross-linked polysiloxane is then added to the bulk subbase material in any suitable ratio, for example, 2-5 parts by weight of the polysiloxane bulk subbase material per part of the cross-linked polysiloxane. The crosslinked polysiloxane is a second precursor that can be polymerized or can react with the first precursor. This mixture is placed in a suitable mold or master containing a negative of the feature pattern 16 when the feature pattern 16 is regenerated in the polysiloxane bulk portion 110 of the stamp 14. Subsequently, the mixture is cured (solidified) for a suitable period of time, for example at least 4 hours, such as 6-12 hours, to form a cured (crosslinked) polysiloxane bulk portion of the stamp 14, which cure is In order to improve the reaction rate of the curing reaction, it is carried out at high temperature. For example, the high temperature at which the curing reaction is performed is selected in the range of 30 ° C to 100 ° C, for example, in the range of 50 ° C to 100 ° C. It has been found that the stamp 14 generated in this manner can be removed without problems from a master containing a negative of the mold or feature pattern 16.

  The curing reaction is used to adjust the (Young) modulus of the polysiloxane bulk portion 110 of the stamp 14. Inclusion of the linear cross-linked polysiloxane chain adjusts the Young's modulus of the polysiloxane bulk portion 110 and thus uses the reaction conditions of the curing reaction, such as the amount of cross-linked polysiloxane, the duration and / or temperature of the curing reaction In addition, the Young's modulus of the polysiloxane bulk portion 110 can be adjusted to a specified Young's modulus, that is, the flexibility or compressibility of the polysiloxane bulk portion 110 can be adjusted. More specifically, the low Young's modulus siloxane consists of a linear chain having a reactive vinyl group at the end, and this reactive vinyl group follows the chain to adjust the Young's modulus of the polysiloxane bulk portion 110. Cross-linked by functionalized linear hydrosiloxane.

At this point it is noted that the crosslinking reaction described above (see Reaction Scheme II) is that of hydrosilylation catalyzed by a vinyl metal complex having a hydrosiloxane type. Hydrosilylation reactions such as those described hereinabove are well known per se (eg, DA Vekki and N. K. in CHEMISTRY AND CHEMICAL TECHNOLOGY, TECHNOLOGY OF ORGANIC SUBSTANCES). See the review titled Metal complex catalyzed hydrosilation of vinyl-with hydrosiloxanes (review) by Skvortsov), usually catalyzed by platinum or rhodium catalysts. Suitable catalysts used in the experiments described in this specification are commercially available from Gelest, Incorporated, such as platinum-cyclovinylmethylsiloxane complex (C ₃ H ₆ OSi) _3-5 Pt ⁰ ; 2% Pt (CAS No. 68585-32-0) or a platinum divinyltetramethyldisiloxane complex in methylvinylsiloxane _{(C 24 H 54 O 3 Pt} 2 Si 6); 2% Pt (CAS number in xylene 68478-92 -2). However, other things can be used. In all cases, care must be taken that the catalyst is not poisoned by the substance, especially its basic organic groups added to the polysiloxane-based material. Lewis acids are generally known to be able to become catalyst poisons. Thus, basic organic groups such as amines are also poisons for such platinum or rhodium catalysts, rendering them ineffective for crosslinking reactions. In the case of the materials indicated herein above, steric hindrance within the portion of the basic organic group appears to be important as to whether the material is compatible with the catalyst. In general, the higher the steric hindrance of the basic group or Lewis base donor atom, the more likely the base will be more compatible with the platinum catalyst. One skilled in the art will know how to select catalysts and / or basic organic groups (such as amines) that are compatible with each other, possibly through experiments combined with steric hindrance criteria.

  All of the compounds in Table 2 were subjected to the above-described enclosure method in which the material was dissolved in uncured PDMS in an amount between 0.5 and 3% by weight relative to the total weight of uncured PDMS and allowed to stand overnight. And then a 1: 1 mixture of HMS-301 and HMS-501 from Gelest, Incorporated was added at a ratio of 1-5 wt. And left overnight. Among the compounds in Table 2, compounds 14, 17, and 18 to 34 were able to perform the curing reaction with platinum as a catalyst satisfactorily, and thus made a rubber body stamp. Any of the other compounds hinders the curing of the stamp material precursor (compounds 1, 2, 4-6, 9, 10, 12, 13, 16, 35 and 36) and is clearly causing catalyst poisons, Or it was not mixed with the precursor base material (compounds 3, 7, 8, 11, 15).

Although not wishing to be bound by theory, a suitable secondary amine for use in the above enclosing method is that R ₁ is hydrogen and R ₂ and R ₃ are branched, unsubstituted or substituted. C ₃ -C ₂₀ alkyl group, an unsubstituted or substituted _C 2 _{-C 20} alkenyl group, an unsubstituted or substituted _C 2 _{-C 20} alkynyl group, an unsubstituted or substituted _C 3 _{-C 20} cycloalkyl group, an unsubstituted or substituted C ₄ -C ₂₀ cycloalkenyl group, an unsubstituted or substituted _C 3 _{-C 20} heterocyclic group, an unsubstituted or substituted _C 6 _{-C 30} aryl group, an unsubstituted or substituted _C 6 _{-C 30} alkylaryl group, an unsubstituted or It appears to be an amine according to formula 8, individually selected from substituted C ₄ -C ₃₀ heteroaryl groups.

In this secondary amine embodiment, R ₂ and R ₃ are individually selected from branched unsubstituted or substituted C ₃ -C ₂₀ alkyl groups and unsubstituted or substituted C ₆ -C ₃₀ alkylaryl groups.

  Preferably, at least one of R2 and R3, and more preferably at least two of these are bound to a nitrogen having at least two other atoms different from H, such as two carbon atoms. Having carbon atoms that are Thus, these R2 and R3 are, for example, isoalkyl having less than 20 C atoms (eg, isopropyl, isobutyl, isopentyl, isohexyl, isoheptyl, isooctyl, isononyl, isodecyl, isoundecyl, isododecyl or isobutyl).

  Clearly, therefore, some secondary amines can be introduced that introduce sufficient steric hindrance to prevent poisoning of the hydrosilylation catalyst. Tertiary amines also satisfy this feature.

Accordingly, tertiary amines suitable for use in the above enclosing method are those in which R _{1 to} R ₃ are linear unsubstituted or substituted C _{2 to} C ₂₀ alkyl groups or branched unsubstituted or substituted C ₃ to C ₂₀ alkyl group, an unsubstituted or substituted _C 2 _{-C 20} alkenyl group, an unsubstituted or substituted _C 2 _{-C 20} alkynyl group, an unsubstituted or substituted _C 3 _{-C 20} cycloalkyl group, an unsubstituted or substituted _C 4 -C ₂₀ cycloalkenyl group, an unsubstituted or substituted _C 3 _{-C 20} heterocyclic group, an unsubstituted or substituted _C 6 _{-C 30} aryl group, an unsubstituted or substituted _C 6 _{-C 30} alkylaryl group, an unsubstituted or substituted _{C 4} They are individually selected from -C ₃₀ heteroaryl group, an amine according to formula 8. In this tertiary amine embodiment, R ₁ -R ₃ are linear unsubstituted or substituted C ₂ -C ₂₀ alkyl groups, or branched unsubstituted or substituted C ₃ -C ₂₀ alkyl groups, and unsubstituted or they are individually selected from substituted _C 6 _{-C 30} alkyl aryl group.

である。 Suitable tertiary amines for use in the above enclosing method are amines according to formula 10:

It is.

In Formula 10, R _{1 to} R ₄ are individually selected from a linear unsubstituted or substituted C _{2 to} C ₂₀ alkyl group, or a branched unsubstituted or substituted C _{3 to} C ₂₀ alkyl group. For example, R _{1 to} R ₄ are individually selected from methyl, ethyl or propyl. In embodiments, R _{1 to} R ₄ are all the same, such as methyl or ethyl.

を含む。 More generally, the basic organic group preferably has a structure according to formula 9:

including.

As used herein, N can be a Lewis acid donor atom and X is selected from the group consisting of oxygen, nitrogen, sulfur and phosphorus, thus X can also serve as a Lewis acid donor atom. . R _{1 to} R ₄ are individually selected from unsubstituted or substituted aryl groups, linear C _{2 to} C ₂₀ alkyl groups, or branched C _{3 to} C ₂₀ alkyl groups, preferably R _{1 to} R ₄ are methyl Individually selected from ethyl, propyl. R _{5 to} R ₇ are individual organic groups, or identical organic groups containing one or more hydrogen atoms, carbon atoms, oxygen atoms, nitrogen atoms and sulfur atoms containing less than 20 carbon atoms; can do. Preferably there are less than 10 carbon atoms. Preferably, R _{5 to} R ₇ are at least two olefinic bonds of formula 9, and one other double bond (C═N, C═O or C═C), and / or at least one other carbon— A group having a conjugated system including a carbon triple bond is formed. Preferably, the conjugated system is an aromatic or heteroaromatic system. Preferably the heteroaromatic system comprises at least two benzene rings.

  These compounds effectively have two donor atoms that enhance their retention of protons or other Lewis acids. Therefore, these compounds provide a strong base that has no formal charge. These compounds are often referred to as superbases.

Since some monoalkylamines and some dialkylamines are clearly poisons of the catalyst, these amines cannot be incorporated directly into the stamp by the above method (see eg compounds 9-13, 16). I), a further method uses protected amines as part of the material. One method of protecting amines is by a reaction using a tert-butyloxycarbonyl (Boc) group. The chemistry for the protection and deprotection of amines using such groups is well known per se and will not be described in detail. One method is to heat a mixture of the amine to be protected and di-tert-butyl dicarbonate (Boc ₂ O) in tetrahydrofuran (THF) at about 40 ° C. Deprotection (resulting in free amine groups) can be performed at ambient temperature, for example by exposing the protected amine (carbamate) to 3M hydrochloric acid. Other methods for protection and deprotection with Boc are used. The method is used to protect one or two hydrogen atoms of the amine and works with primary and secondary amines. For example, R.A. Varala, S .; Nuvula, S.M. R. Adapa, J. et al. Org. Chem. 2006, 71, 8283-8286. The protected amine can then be used while curing the stamp material precursor, such as the polysiloxane material described above.

  Compound 30 was used to test the Boc protection method with a stamp. It was purchased as is and was successfully constructed as described above, because it did not poison the hydrosilylation catalyst during curing. The Boc group was removed by exposing the stamp containing compound 30 to 3M HCl in water for 60 minutes at room temperature. The Boc group results in carbon dioxide and t-butanol upon deprotection that do not interfere with the stamp function as a by-product. This test was performed several times and some stamps were washed with isopropanol and water after exposure to HCl and dried in an oven at 90 ° C. A portion of the stamp was exposed to a base solution for a period of time after its exposure to HCl. The base can be sodium bicarbonate, or brine solution, or even sodium hydroxide solution. This is done to remove HCl bound to the free amine group.

  Thus, by using this method, all amines can be effectively incorporated using in situ curing methods.

  In the case of a PDMS stamp formed by the above enclosing method, a 1: 1 (by weight) TMOS--70-250 nm thick on a silicon substrate with and without EEOL having a pH of about 4.5. It was found that when the stamp was brought into contact with the MTMS sol-gel layer, all the stamps effectively solidified the TMOS-MTMS sol-gel layer in less than 60 seconds. For example, in the case of some compounds (all tertiary amines) such as 14, 22-24, this is in the fidelity of the feature pattern formed in the solidified TMOS-MTMS sol-gel layer, It can be repeated at least 50 times without significant increase in cure time and without observable degradation, so the basic organic amine can be substantially contained within the PDMS stamp without degrading its feature pattern 16. It has been demonstrated that

  As a comparative example, a PDMS stamp without surrounding material was used to imprint a 70-250 nm thick TMOS-MTMS sol-gel layer on a silicon substrate having a pH of about 4.5 with and without EEOL. used. In this comparative example, it took about 20 minutes to complete the sol-gel crosslinking. This is possibly because, under acidic conditions, mainly linear chains are formed in the polycondensation reaction, whereas under basic conditions, mainly cross-linked chains are formed during the polymerization reaction, resulting in a base. This can be explained by the fact that the time required for forming the crosslinked polysiloxane network is shortened by the catalytic action of the polycondensation reaction. More generally, a base-catalyzed alkoxysilane polycondensation reaction is faster than an acid-catalyzed alkoxysilane polycondensation reaction.

  The excellent retention of the basic compound in the stamp 14 is due to the fact that in the above experiment, the sol-gel residue remaining on the stamp after the imprinting process is immersed in a 1% HF solution for 2 minutes and deionized. It is further demonstrated that it can be removed by washing with water and then baking the stamp on a 70 ° C. hotplate for 15 minutes. After this cleaning procedure, the catalytic activity of the stamp in subsequent imprinting cycles was not affected.

  In an embodiment, the stamp 14 includes a separate surface layer 120 as previously described. In this embodiment, the surface layer 120 is applied to the polysiloxane bulk material in which the basic organic amine is dissolved before the polysiloxane bulk material is cured, after the polysiloxane bulk material is partially cured, or after the polysiloxane bulk material is cured. Grafted or glued. This has the advantage that the surface layer 120 containing the feature pattern 16 is not exposed to the basic organic amine during its manufacture, for example during its curing. Thus, the interference of basic organic amines during the curing reaction of the surface layer is avoided, so that the desired elastomeric properties of this surface layer are protected. Instead, the basic organic amine diffuses into the surface layer 120 after its grafting or adhesion to the polysiloxane bulk 110. For this reason, the surface layer 120 is preferably grafted or adhered to the polysiloxane bulk 110 prior to (before completion of) the polysiloxane bulk 110, resulting in a high temperature at which the curing reaction takes place, for example, A temperature in the range of 30-100 ° C. can accelerate the diffusion process so that when the elastomeric stamp 14 comes into contact with the imprinting composition layer 12, sufficient basic organic amine is present in the surface layer 120. It is ensured that the polymerization reaction in the imprinting composition layer 12 is effectively catalyzed.

  In the experiment, compound 22 was surrounded in a soft PDMS stamp layer (Young's modulus of about 2-3 MPa) in amounts of 2%, 1%, 0.5%, 0.25 and 0.125%, after which The X-PDMS layer (Young's modulus of about 70-80 MPa) is bonded to the soft PDMS stamp layer. The layer stack was then cured at 50 ° C. for 2-24 hours. Immediately after curing, the stamp thus obtained having a total thickness of 500 to 1000 microns is deposited on a silicon substrate with the desired cross-linking of the sol-gel layer achieved within 30 seconds to a thickness of 60 to 150 nm. Of the TMOS-MTMS sol-gel layer.

  In the above embodiment, the basic organic amine preferably has a vapor pressure not exceeding 0.2 mbar at 25 ° C. to avoid excessive evaporation of the basic organic material from the stamp 14. For example, during the positioning of the stamp 14 on the substrate 10, such evaporation in the vicinity of the imprinting composition 12 can cause undesirable migration of the basic organic amine from the stamp 14 to the imprinting composition 12. This undesired migration can cause premature polymerization of the imprinting composition 12. Such premature solidification of the imprinting composition 12 can inhibit the regeneration (highly fidelity) of the feature pattern 16 in the imprinting composition 12, as already described. In order to avoid significant evaporation, larger molar weight materials are generally preferred. That is, for example, the substituents of successfully included compounds such as monoalkylamines, dialkylamines and trialkylamines in the stamp have more than 5 carbon atoms. Preferably, it will be more than 10, more preferably more than 15, or more than 20. For example, the secondary or tertiary amines described above having such a number of compounds can be used. A person skilled in the art can, for example, select the relevant one from Table 2 according to these concepts.

  Stamps of the invention having substrates incorporated either by impregnation or by build-in by reaction using other reactive crosslinkable materials and reaction schemes other than those described hereinabove Can be reached.

  However, another method of manufacturing a stamp according to the present invention is that the curing of the stamp body material is a substance having organic basic groups as described hereinabove for stamp bodies of polysiloxanes and organic amine compounds, for example. Build on the method done in the presence of. This is called a built-in method. In this method, the material is selected to include, for example, reactive groups that react with the elastomer body precursor material to form an organic polymer bulk portion and / or surface layer while the elastomer body precursor material is cured. . Using this approach, the substance, and the basic organic groups that accompany it, can be permanently linked (by covalent bonds) to the elastomeric stamp body.

  This method is illustrated with respect to the polysiloxane stamp described hereinabove. That is, the PDMS base material (precursor) having vinyl end groups was mixed with any one of the compounds 30 to 36 in Table 2. The concentration or amount used was the same as that used in the curing method described hereinabove. Most of these compounds also have vinyl end groups, with the exception of compounds 35 and 36, which have trialkoxysilane groups as reactive groups. Compounds 30-32 were added to the entire curable mixture in an amount of 1% by weight, whereas in the case of compounds 33-36 these amounts were 3%. To this mixture was added a cross-linked polysiloxane having hydrosilane groups and a hydrosilylation catalyst as performed for the curing experiments described above. The amounts of base material (first precursor) and crosslinker polysiloxane (second precursor) are as used in the inclusion method described hereinabove.

  Elastomer-solidified polysiloxane bulk portion with added compound, all of the precursor (curable) mixture except those having compounds 35 and 36 are bonded to the crosslinked polysiloxane backbone of the elastomeric stamp body Brought about. The stiffness of the stamp with compounds 33 and 34 was somewhat higher and did not lead to a very useful stamp. Vinyl end groups are well involved in the hydrosilylation reaction, but trialkoxysilane compounds 35 and 36 were not cross-linked by alkoxysilane.

  Again, as described hereinabove, compound 30 is a protected amine, which as described hereinabove, after curing of the deprotected stamp material. It was a thing.

  PDMS in the latter method is soft PDMS (such as those based on Sylgard and those based on linear substrates as described above) or X-PDMS based on branched substrates. Somewhat stiffer PDMS can be achieved. Either of them can be mixed with a linear hydrosilane containing a second precursor.

  If the stamp is designated to have an organic surface layer, this is a layer that preferably contains a bound basic compound. Therefore, to achieve this, the methods used in the inclusion method described herein above can be used for the incorporation method.

  Again, it will be apparent that the nature of the basic organic group must be selected so as not to interfere with the curing reaction. Thus, sterically hindered amines will work best when hydrosilylation is used for curing and crosslinking reactions. Similarly protected amines or other protected Lewis acid bases can be used according to the invention.

  Stamps obtained with the bound base were tested in the imprint process using a test situation similar to that used above. They all showed an increase in solidification rate upon imprinting compared to similar stamps that did not have an incorporated compound, but compounds 31-34 solidify faster than stamps with compounds 35 and 36. Brought about. Compound 32 achieved good speed, but Compound 31 provided the best cure and stamp characteristics.

  The present invention having an elastomeric stamp containing a suitable base to promote solidification of the imprinting solution was discussed in detail with respect to an elastomeric stamp body comprising a polysiloxane bulk portion. It will be apparent that other elastomers and rubbers may be used without departing from the inventive concept. A number of such materials are available in the prior art and commercially. In fact, for the impregnation method, such rubber must be permeable. Otherwise, it is necessary to perform an inclusion process by curing (polymerization) of the bulk partial precursor due to the presence of a base or protected base in situ. These are not explicitly described herein, but the invention as implemented can still work.

  The above embodiments are illustrative rather than limiting of the invention, and those skilled in the art can design numerous alternative embodiments without departing from the scope of the appended claims. It should be noted that it can be done. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. The word “comprising” does not exclude the presence of elements or steps other than those listed in a claim. The word “a” or “an” preceding an element does not exclude the presence of a plurality of such elements. The present invention can be implemented by hardware including several separate elements. In the device claim enumerating several means, several of these means can be embodied by one and the same item of hardware. The mere fact that certain measures are recited in mutually different dependent claims does not merely indicate that a combination of these measures cannot be used to provide benefit.

Claims (30)

A stamp for an imprint lithography process comprising an elastomeric stamp body having an organic polymer bulk portion and a patterned surface having a relief feature pattern for imprinting an imprinting composition,
The stamp, wherein the elastomeric stamp body comprises an amount of at least one basic organic group that can promote solidification of the imprinting composition upon contact with the patterned surface.   The stamp of claim 1 wherein the basic organic group is an uncharged Lewis base having at least one donor atom selected from the group consisting of oxygen, nitrogen, sulfur and phosphorus.   The stamp according to claim 2, wherein the donor atom is a nitrogen atom.   The stamp according to claim 1 or 2, wherein the basic organic group has a pKa between 8-12. The basic organic group is a structure according to Formula 8:

Wherein N is the donor atom, and R _{1 to} R ₃ are hydrogen, unsubstituted or substituted C _{2 to} C ₂₀ alkyl group, unsubstituted or substituted C _{2 to} C ₂₀ alkenyl group, unsubstituted or substituted _C 2 _{-C 20} alkynyl group, an unsubstituted or substituted _C 3 _{-C 20} cycloalkyl group, an unsubstituted or substituted _C 4 _{-C 20} cycloalkenyl group, an unsubstituted or substituted _C 3 _{-C 20} heterocyclic group, no unsubstituted or substituted _C 6 _{-C 30} aryl group, an unsubstituted or substituted _C 6 _{-C 30} alkylaryl group, but individually selected from unsubstituted or substituted _C 4 _{-C 30} heteroaryl group, provided _that, R 1 to R ₃ is provided that not all are hydrogen, and at least two of R _{1 to} R ₃ are the same unsubstituted or substituted C _{3 to} C ₂₀ cycloalkyl group, unsubstituted or substituted C _{4 to} C ₂₀ Sik Alkenyl group, forms part of an unsubstituted or substituted _C 3 _{-C 20} heterocyclic group, an unsubstituted or substituted _C 6 _{-C 30} aryl group, or an unsubstituted or substituted _C 4 _{-C 30} heteroaryl group, claims The stamp according to 3 or 4. R _{1 to} R ₃ are hydrogen, linear unsubstituted or substituted C _{6 to} C ₂₀ alkyl group, or branched unsubstituted or substituted C _{3 to} C ₂₀ alkyl group, unsubstituted or substituted C _{2 to} C ₂₀ alkenyl. group, an unsubstituted or substituted _C 2 _{-C 20} alkynyl group, an unsubstituted or substituted _C 3 _{-C 20} cycloalkyl group, an unsubstituted or substituted _C 4 _{-C 20} cycloalkenyl group, an unsubstituted or substituted _C 3 _{-C 20} heterocyclic cyclic group, an unsubstituted or substituted _C 6 _{-C 30} aryl group, an unsubstituted or substituted _C 6 _{-C 30} alkylaryl group, but individually selected from unsubstituted or substituted _C 4 _{-C 30} heteroaryl group, provided that , with the proviso that only one hydrogen of _R 1 to R _3, preferably _R 1 to R ₃ are hydrogen, a linear unsubstituted or substituted _C 6 _{-C 20} a Kill group, branched unsubstituted or substituted _C 3 _{-C 20} alkyl group, or an unsubstituted or are selected independently from substituted _C 6 _{-C 30} alkyl aryl group, provided _that only one of R 1 to R ₃ 6. The stamp according to claim 5, wherein the stamp is hydrogen. R _{1 to} R ₃ are linear unsubstituted or substituted C _{2 to} C ₂₀ alkyl groups, or branched unsubstituted or substituted C _{3 to} C ₂₀ alkyl groups, unsubstituted or substituted C _{2 to} C ₂₀ alkenyl groups, unsubstituted or substituted _C 2 _{-C 20} alkynyl group, an unsubstituted or substituted _C 3 _{-C 20} cycloalkyl group, an unsubstituted or substituted _C 4 _{-C 20} cycloalkenyl group, an unsubstituted or substituted _C 3 _{-C 20} heterocyclic group, an unsubstituted or substituted _C 6 _{-C 30} aryl group, an unsubstituted or substituted _C 6 _{-C 30} alkyl aryl group, selected independently from unsubstituted or substituted _C 4 _{-C 30} heteroaryl group, preferably _R 1 ~ R ₃ is a linear unsubstituted or substituted _C 2 _{-C 20} alkyl group, branched unsubstituted or substituted _C 3 _{-C 20} alkyl group, or unsubstituted substituted or Is individually selected from substituted C ₆ -C ₃₀ alkylaryl group, stamp of claim 6. The basic organic group is a structure according to Formula 9:

Wherein N is the donor atom, X is selected from the group consisting of oxygen, nitrogen, sulfur and phosphorus, and R _{1 to} R ₄ are linear unsubstituted or substituted C _{2 to} C ₂₀ individually selected from an alkyl group or branched unsubstituted or substituted _C 3 _{-C 20} alkyl group, _preferably, R 1 to R ₄ are individually selected from methyl, ethyl or _propyl, R 5 to R ₇ is An individual organic group or an identical organic group containing less than 20 carbon atoms and containing one or more hydrogen atoms, carbon atoms, oxygen atoms, nitrogen atoms and sulfur atoms. The stamp according to 3 or 4. The structure is represented by formula 10:

The stamp according to claim 8, wherein The basic organic group is a portion of the material not covalently bonded to the elastomeric stamp body,
The stamp according to any one of claims 1 to 9.   11. The stamp of claim 10, wherein the elastomeric stamp body includes the material in an amount of at least 0.1% by weight relative to the total weight of the elastomeric stamp body.   The stamp according to claim 10 or 11, wherein the substance has a vapor pressure of 0.2 mbar or less at a temperature of 25 ° C. The basic organic group is covalently bonded to the organic polymer bulk portion, or
The elastomeric stamp body includes an organic polymer surface layer adhered to the organic polymer bulk portion, and the patterned surface forms a portion of the organic polymer surface layer, the amount of basic organic groups The stamp according to any one of claims 1 to 9, wherein at least a part is covalently bonded to the organic polymer surface layer.   The elastomeric stamp body, or the organic polymer bulk portion, comprises or comprises a material selected from the group consisting of at least one polysiloxane, at least one per-fluoro-poly-ether or mixtures thereof. The stamp according to any one of claims 1 to 13.   The elastomeric stamp body comprises or consists of an organic polymer surface layer adhered to the organic polymer bulk portion, the patterned surface layer being part of the organic polymer surface layer, and the organic polymer surface layer 15 comprises or consists of a material selected from the group consisting of at least one polysiloxane, at least one per-fluoro-poly-ether (PFPE) or mixtures thereof. The stamp according to any one of the above.   The stamp according to any one of claims 14 and 15, wherein the polysiloxane comprises or consists of polydimethylsiloxane (PDMS).   The polymer organic bulk portion comprises or consists of an organic polymer surface layer adhered to an organic polymer portion surface layer, and the patterned surface layer forms part of the organic polymer surface layer, and the organic polymer The stamp according to any one of claims 1 to 16, wherein the surface layer has a Young's modulus greater than that of the organic polymer partial surface layer.   18. A stamp according to any preceding claim, further comprising a carrier, wherein the organic polymer bulk portion is patterned either directly or via at least one further layer. A stamp which is bound to the main surface of the carrier distal to the surface. Providing an elastomeric stamp body having an organic polymer bulk portion and a relief surface;
Impregnating the elastomeric stamp body with an amount of a basic organic material to provide an impregnated elastomeric stamp body, wherein the imprinting is performed when the basic organic material contacts the patterned surface. Including a basic organic group that promotes solidification of the composition; and removing at least a portion of the solvent from the impregnated elastomeric stamp body to leave the elastomeric stamp body containing the basic organic material. A method for manufacturing the stamp according to any one of claims 1 to 18. The organic polymer bulk portion, or containing a polysiloxane, or it now, said step of soaking is preferably an organic solvent which is C ₁ -C ₆ aliphatic alcohol or mixtures thereof, said basic certain amount The method according to claim 19, wherein the method is performed by dissolving an organic substance. Each comprising one or more precursors comprising at least one first reactive group, which can be polymerized to form said organic polymer bulk portion, and said basic organic group, or Providing a mixture of materials containing protected basic organic groups that do not substantially inhibit the polymerization of one or more precursors;
Polymerizing the organic polymer bulk portion precursor to form the organic polymer bulk portion surrounding the material therein, and where the material comprises the protected basic organic group, The method for producing a stamp according to any one of claims 1 to 18, comprising a step of deprotecting a basic organic group to provide the basic organic group. The one or more precursors are
A first polysiloxane precursor having at least two groups as the at least one first reactive group, each of the at least two groups comprising an unsaturated bond, and each of the at least two groups Wherein the first polysiloxane precursor selected from the group consisting of alkynes, alkenes, vinyls, aldehydes, ketones and imines, and a second polysiloxane precursor having at least two hydrosilane groups,
The mixture is
A hydrosilylation catalyst that catalyzes the addition of a hydrosilane group to the unsaturated bond;
The method of claim 21, wherein the polymerizing comprises causing the addition of the hydrosilane group to the unsaturated bond, thereby forming the organic polymer bulk portion. The substance further comprises at least one second reactive group for reacting with the first reactive group;
22. The method of claim 21, wherein the polymerizing comprises reacting between the first reactive group and the second reactive group, thereby binding the material to the organic polymer bulk portion. The method described. The one or more precursors are
A first polysiloxane precursor having at least two groups as the at least one first reactive group, each of the at least two groups comprising an unsaturated bond, and each of the at least two groups Wherein the first polysiloxane precursor is selected from the group consisting of alkynes, alkenes, vinyls, aldehydes, ketones and imines, and a second polysiloxane precursor having at least two hydrosilane groups,
Including
The at least one second reactive group is selected from the group consisting of alkynes, alkenes, vinyls, aldehydes, ketones, imines and hydrosilanes;
The mixture is
A hydrosilylation catalyst that catalyzes the addition of a hydrosilane group to the unsaturated bond;
24. The method of claim 23, wherein the polymerizing comprises causing the addition of the hydrosilane group to the unsaturated bond, thereby forming the organic polymer bulk portion. A first portion comprising one or more precursors, wherein each of the one or more precursors is polymerized to form the organic polymer bulk portion. The first moiety having a reactive group that can be protected, and the protected basic organic that contains the basic organic group or does not substantially inhibit the polymerization of the one or more precursors 19. A kit of parts for producing a stamp according to any one of claims 1 to 18, comprising a second part comprising a substance comprising a group. The one or more precursors are
A first polysiloxane precursor having at least two groups as at least one first reactive group, wherein each of the at least two groups contains an unsaturated bond, and each of the at least two groups is The first polysiloxane precursor selected from the group consisting of: alkyne, alkene, vinyl, aldehyde, ketone and imine;
A second polysiloxane precursor having at least two hydrosilane groups;
26. A parts kit according to claim 25, comprising a hydrosilylation catalyst for catalyzing the addition of hydrosilane groups to the unsaturated bonds.   27. A parts kit according to claim 26, wherein the substance comprises a reactive group selected from the group consisting of alkynes, alkenes, vinyls, aldehydes, ketones, imines and hydrosilanes. Providing a layer of an imprinting composition capable of solidifying under the influence of an organic basic group;
19. Contacting the layer with a stamp according to any one of claims 1 to 18 so that the relief feature pattern is imprinted on the layer of the imprinting composition;
Maintaining contact between the layer of the imprinting composition and the stamp until the imprinted composition reaches a desired degree of solidification; and from the solidified layer of the imprinting composition A method for forming a pattern forming layer, comprising: taking out the stamp and obtaining a pattern forming layer.   29. The method of claim 28, wherein the imprinting composition comprises or consists of a sol-gel based imprinting composition, such as an alkoxysiloxane based imprinting composition.   20. Use of a stamp according to any one of claims 1 to 19 in an imprint lithography process for forming a patterned layer.

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